1. Field of the Invention
The present invention relates to a digital broadcast system, and more particularly, to a digital broadcast transmitting/receiving system and a method for processing data.
2. Discussion of the Related Art
Presently, the technology for processing digital signals is being developed at a vast rate, and, as a larger number of the population uses the Internet, digital electric appliances, computers, and the Internet are being integrated. Therefore, in order to meet with the various requirements of the users, a system that can add video/audio data through a digital broadcasting (or television) channel so as to transmit diverse supplemental information needs to be developed.
Some users may assume that supplemental data broadcasting would be applied by using a PC card or a portable device having a simple in-door antenna attached thereto. However, when used indoors, the intensity of the signals may decrease due to a blockage caused by the walls or disturbance caused by approaching or proximate mobile objects. Accordingly, the performance of the received digital signals may be deteriorated due to a ghost effect and noise caused by reflected waves. Therefore, a system highly resistant to (or robust against) ghost effects and noise is required to be developed. Particularly, in order for the supplemental data to be used in portable and mobile broadcast receivers, a higher degree of resistance (or robustness) against channel interruption and noise is required.
The supplemental data are generally transmitted by a time-division method through the same channel as the MPEG video/audio data. However, with the advent of digital broadcasting, ATSC VSB digital television receivers that receive only MPEG video/audio data are already supplied to the market. Therefore, the supplemental data that are transmitted through the same channel as the MPEG video/audio data should not influence the conventional ATSC VSB receivers that are provided in the market. In other words, this may be defined as ATSC VSB compatibility, and the supplemental data broadcast system should be compatible with the ATSC VSB system. Herein, the supplemental data may also be referred to as enhanced data or EVSB data. Furthermore, as the number of possessed automobiles (or cars) is in constant increase, and with the influence of the working-5-days-a-week policy (which eventually leads to an increase in the usage of cars), the need for traffic information is also increasing accordingly.